1. Field of the Invention
The present invention relates to an improved security control barrier for use in controlling ingress and egress to entranceways, exit ways, driveways, and parking spots. The device consists of a telescoping bollard inserted into a casing imbedded below ground and a locking mechanism for securing the telescoping bollard in the extended and retracted positions. The invention also serves as an effective anti-theft device.
2. Description of the Related Art
Various devices employed to control access to parking spaces and ingress/egress to entranceways have been proposed. Often found are retractable or articulating devices which consists of a post or barrier frame that is pivotally connected to a fixed base. The post or barrier frame is then raised from a near horizontal position when retracted, to a vertical position when employed. U.S. Pat. No. 4,858,328 issued to Ellgass is one such device. A disadvantage of such devices is that they are exposed above ground making them subject to vandalism and excessive damage from vehicles transgressing over them, and therefore require frequent repair or replacement.
Other prior art include systems which employ bollards encased below the surface. U.S. Pat. No. 4,919,563 issued to Stice and U.S. Pat. No. 5,476,338 issued to Alberts are exemplary of this art. The Stice and Alberts devices are relatively complicated employing a worm gear/screw lift mechanisms and are dependent upon underground motors and external power sources (Electrical Current or Battery) for their operation. Underground environmental exposure to subterranean electronic devices is undesirable. Both devices contain a large number of parts and components. Maintenance for these type of devices is rather extensive.
Prior art such as U.S. Pat. No. 4,003,161 issued to Collins is designed as a retractable barrier without a lift assistance mechanism and is employed using human power. As a result devices of this art are disadvantaged by being of lighter less sturdy construction so as to enable a human to raise the device solely with manual power.
U.S. Pat. No. 4,576,508 issued to Dickenson is described as an anti-terror barricade capable of stopping the movement of vehicles. This art employs a below the surface bollard raised by a hydraulic lift mechanism. The hydraulic lift mechanism is activated through an electrical control system. Again, underground environmental exposure to a subterranean electronic device and subterranean hydraulic system is undesirable. Maintenance for hydraulic systems is extensive. Operation based upon two dependent power sources (electrical power and hydraulic power) degrades reliability. U.S. Pat. No. 4,715,742 issued to Dickinson is also an anti-terror barricade intended to stop the movement of vehicles. This below the surface bollard is raised by the stored energy of a metal coil spring. The coil spring is released and locked through an electronically or manually engaged bolt. The bolt and the control box which houses the bolt are recessed just below grade level. Access to the control is through a locked cover. Both the bolt and the cover to the control box are located too close to the surface and could result in sabotage or vandalism to the device. Both of these Dickinson systems are anti-terror devices and as such are intended to withstand severe impacts. As a result, the increased costs of creating this capability make widespread use of the devices as general vehicle parking or passageway security barriers impracticable.
Further art also include telescoping posts which are raised exclusively through the stored energy of pneumatic or hydraulic springs. These devices are affected often by temperature variations. They are disadvantaged, in that in extremely cold temperatures the stored energy of the spring is severely degraded to the point where effective operation of the device through the exclusive power of the spring may not be feasible or to the point where an extremely powerful spring is required to operate in cold temperatures. Such a powerful spring would require extreme manual pressure to retract the device making the retraction very difficult.
An object of the present invention is to provide a gas spring lift assisted telescoping security bollard that is functional within a wide temperature range, a telescoping bollard which displays great strength and stability, and one that is easy to operate and install. Accordingly, there is also a need for such a device that has few parts and is easy to repair.
Another object of the bollard is to provide an anti-theft device which is extremely sturdy, stable, and one which would require a very long time to defeat thus resulting in a prolonged exposure of someone committing a criminal act.
A further intent of the present art is to provide a stable security bollard that is easily installed, and easy to maintain and reliable in its employment.
A further object of the present invention is to provide a security bollard that is of simple design, has few parts and components, and one that is economically priced.
Still a further object of this invention is to provide a telescoping bollard that guarantees proper drainage and one that will not have its operation be adversely affected by dirt and debris or extreme climatic conditions.
Still a further object of the present invention is to present a telescoping bollard that is locked in both the extended and retracted positions.
These and other objects are satisfied by the device of the present invention.